1. Field of the Invention
This invention relates to modified normally liquid, water-soluble polyoxyalkylene polyamines and to a process by which they may be prepared. More particularly, this invention relates to normally liquid, water-soluble polyoxyethylene polyamines modified by the inclusion of oxypropylene groups and to a special process to be used in preparing the modified polyamines.
Still more particularly, this invention is directed to normally liquid, water-soluble poly(oxyethylene/oxypropylene)polyamine products having an average molecular weight of about 1000 to about 8000 and a functionality of about 2 to about 4 which are prepared by adding predetermined amounts of ethylene oxide and propylene oxide to an alkoxylation susceptible polyhydric alcohol initiator to form an intermediate which is then propoxylated to form a precursor polyol which, in turn, is reductively aminated in the presence of a hydrogenation/dehydrogenation catalyst to provide the desired normally liquid, water-soluble poly(oxyethylene/oxypropylene) polyamine.
The poly(oxyethylene/oxypropylene) polyamine may be used to form an aqueous solution containing from about 1 to about 50 wt.% of the polyamine. The aqueous solution of the polyamine may be used as such, e.g., as a major component of a functional fluid such as a hydraulic fluid, or as a feedstock for a further chemical processing step.
The poly(oxyethylene/oxypropylene) precursor polyols of the present invention are also water soluble liquids at ambient temperatures and may be used as feedstocks for the preparation of the poly(oxyethylene/oxypropylene) polyamines of the present invention or may be used to prepare aqueous solutions of the poly(oxyethylene/oxypropylene) polyol containing from about 1 to about 50 wt.% of the polyol.
2. Prior Art
Yeakey U.S. Pat. No. 3,654,370 discloses a process for the preparation of polyoxyalkylene polyamines by the reaction of a polyoxyalkylene polyol feedstock with ammonia in the presence of hydrogen under reductive amination conditions to provide the corresponding polyoxyalkylene polyamine.
Lee et al. U.S. Pat. No. 3,236,895 discloses a process for producing polyoxyalkylene polyamines such as polyoxyalkylene diamines by reacting a polyoxyalkylene diol with ammonia in the presence of hydrogen.
British Patent No. 934,636 also discloses the preparation of oxyalkylene amines by reacting polyoxyalkylene glycol ethers with ammonia using a hydrogenation/dehydrogenation catalyst.
Boettger et al. U.S. Pat. No. 4,014,933 discloses the reaction of alcohols with ammonia at elevated temperatures and pressures in the presence of hydrogen and a hydrogenation catalyst.
Nickel/copper/chromia catalysts of the type preferred by Yeakey are disclosed in Moss U. S. Patent No. 3,152,998.